Many of complexes in which a chiral tertiary phosphine is coordinated to a metallic element, e.g., rhodium, ruthenium, palladium, etc., exhibit excellent performances as catalysts for asymmetric syntheses. In an attempt of improving catalytic performances of these metal-phosphine complexes, a number of phosphine compounds having special structures have hitherto been developed as recited, e.g., in Nihon Kagakukai (ed.), Kagaku Sosetsu, Vol. 32, pp. 237-238, "Yuki Kinzoku Sakutai no Kagaku" (1982), Synthesis (Reviews), pp. 85-116 (1981), etc.
2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl (hereinafter abbreviated as BINAP) disclosed in U.S. Pat. Nos. 4,564,708 and 4,605,750, and Japanese Patent Application (OPI) No. 61937/80 (the term "OPI" as used herein meaning "unexamined published application") is one of the excellent phosphine compounds so far developed. However, the above described Japanese patent application referrs to substituted BINAP only by citing some examples of 3,3'-substituted BINAP.
Further, none of the conventionally proposed phosphine compounds is capable of providing catalysts which fully satisfy the requirements of selectivity, conversion, and duration in asymmetric syntheses. It has been, therefore, keenly demanded to develop a phosphine compound providing catalysts for asymmetric syntheses that exhibit markedly improved catalytic performances over the conventional ones.
The inventors previously studied aiming at development of phosphine compounds forming satisfactory catalysts for asymmetric synthesis, and found p-tolyl BINAP, i.e., (2,2'-bis(di-p-tolylphosphino)-1,1'-binaphthyl, as disclosed in U.S. Pat. No. 4,604,474 (corresponding to Japanese Patent Application (OPI) No. 199898/85).